Method for making a reinforced absorbable multilayered fabric for use in medical devices

ABSTRACT

The present invention is directed to a method of making a multilayered fabric comprising a first absorbable nonwoven fabric and a second absorbable woven or knitted fabric.

This application claims priority from U.S. Provisional Application Ser.No. 60/620624, filed on 20 Oct. 2004.

FIELD OF THE INVENTION

The present invention relates to a method for making a reinforcedabsorbable multilayered fabric that is useful in medical devices.

BACKGROUND OF THE INVENTION

It is generally known to use multilayered fabrics in connection withmedical procedures. For example, multilayered fabrics are used as allpurpose pads, wound dressings, surgical meshes, including hernia repairmeshes, adhesion prevention meshes and tissue reinforcement meshes,defect closure devices, and hemostats.

U.S. Pat. No. 5,593,441 to Lichtenstein et al describes a compositeprosthesis preferably having a sheet of polypropylene mesh that allowstissue in-growth, such as Marlex® mesh. This reference discloses thatother surgical materials that are suitable for tissue reinforcement anddefect closure may be utilized, including absorbable meshes such as apolyglactin 910 (Vicryl®) mesh. The composite prosthesis of Lichtensteinet al also has an adhesion barrier, preferably a sheet of siliconeelastomer. This reference generally suggests that that an oxidizedregenerated cellulose such as Interceed® (TC7) absorbable adhesionbarrier (commercially available from Ethicon, Inc., in Somerville, N.J.)may be used as the adhesion barrier to produce a composite prosthesishaving short term effectiveness. The composite prosthesis ofLichtenstein et al is described for use in reinforcing and repairing aweakened muscular wall while limiting the incidence of postoperativeadhesions.

U.S. Pat. No. 5,686,090 to Schilder et al describes the use of a fleecein combination with a nonabsorbable or absorbable film to preventmis-growths to adjacent tissue and to reduce adhesions. Schilder et algenerally discloses that polypropylene, polyester, polyglactin,polydioxanone or poliglecaprone 25 may be used as the fleece material orthe film material. The term “fleece” as used in this reference isdescribed by its porosity, which is described as being in the rangebetween 100 and 1000 l/(m²s) gas flow, measured with an inlet pressureof 200 Pa, a test surface of 50 cm² and a test thickness of 1 mm. Thecomposite of Schilder et al is generally described as being amultilayered implant.

Additionally, multilayered fabrics are useful for tissue engineering andorthopedic applications. The recent emergence of tissue engineeringoffers numerous approaches to repair and regenerate damaged/diseasedtissue. Tissue engineering strategies have explored the use ofbiomaterials that ultimately can restore or improve tissue function. Theuse of colonizable and remodelable scaffolding materials has beenstudied extensively as tissue templates, conduits, barriers andreservoirs. In particular, synthetic and natural materials in the formof foams, sponges, gels, hydrogels, textiles, and nonwovens have beenused in vitro and in vivo to reconstruct/regenerate biological tissue,as well as deliver chemotactic agents for inducing tissue growth. Thedifferent forms of scaffolds may be laminated to form a multilayeredtissue engineering scaffold.

However, the prior art fails to describe or suggest a reinforcedabsorbable multilayered fabric having a first absorbable nonwoven fabricreinforced by a second absorbable woven or knitted fabric.

As used herein, the term “nonwoven fabric” includes, but is not limitedto, bonded fabrics, formed fabrics, or engineered fabrics, that aremanufactured by processes other than spinning, weaving or knitting. Morespecifically, the term “nonwoven fabric” refers to a porous,textile-like material, usually in flat sheet form, composed primarily orentirely of staple fibers assembled in a web, sheet or batt. Thestructure of the nonwoven fabric is based on the arrangement of, forexample, staple fibers that are typically arranged more or lessrandomly. The tensile, stress-strain and tactile properties of thenonwoven fabric ordinarily stem from fiber to fiber friction created byentanglement and reinforcement of, for example, staple fibers, and/orfrom adhesive, chemical or physical bonding. Notwithstanding, the rawmaterials used to manufacture the nonwoven fabric may be yarns, scrims,netting, or filaments made by processes that include spinning, weavingor knitting.

SUMMARY OF THE INVENTION

The present invention is directed to a method for making a reinforcedabsorbable multilayered fabric comprising a first absorbable nonwovenfabric reinforced by a second absorbable woven or knitted fabric. Moreparticularly, the first absorbable nonwoven fabric comprises fiberscomprising aliphatic polyester polymers, copolymers, or blends thereof;while the second absorbable woven or knitted fabric comprises oxidizedregenerated cellulose fibers.

DETAILED DESCRIPTION OF THE INVENTION

The reinforced absorbable multilayered fabric generally comprises anonwoven fabric and a reinforcement fabric. The reinforcement fabricprovides a backing to which the nonwoven fabric may be attached, eitherdirectly or indirectly.

The nonwoven fabric functions as the first absorbable nonwoven fabric ofthe reinforced absorbable multilayered fabric described herein. Thefirst absorbable nonwoven fabric is comprised of fibers comprisingaliphatic polyester polymers, copolymers, or blends thereof. Thealiphatic polyesters are typically synthesized in a ring openingpolymerization of monomers including, but not limited to, lactic acid,lactide (including L-, D-, meso and D, L mixtures), glycolic acid,glycolide, ε-caprolactone, p-dioxanone (1,4-dioxan-2-one), andtrimethylene carbonate (1,3-dioxan-2-one).

Preferably, the first absorbable nonwoven fabric comprises a copolymerof glycolide and lactide, in an amount ranging from about 70 to 95% bymolar basis of glycolide and the remainder lactide.

In an alternative embodiment, the first absorbable nonwoven fabriccomprises fibers comprised of aliphatic polyester polymers, copolymers,or blends thereof, in combination with oxidized polysaccharide fibers.

Preferably, the nonwoven fabric is made by processes other thanspinning, weaving or knitting. For example, the nonwoven fabric may beprepared from yarn, scrims, netting or filaments that have been made byprocesses that include spinning, weaving or knitting. The yarn, scrims,netting and/or filaments are crimped to enhance entanglement with eachother and attachment to the second absorbable woven or knitted fabric.Such crimped yarn, scrims, netting and/or filaments may then be cut intostaple that is long enough to entangle. The staple may be between about0.1 and 3.0 inches long, preferably between about 0.75 and 2.5 inches,and most preferably between about 1.5 and 2.0 inches. The staple may becarded to create a nonwoven batt, which may be then needlepunched orcalendared into the first absorbable nonwoven fabric. Additionally, thestaple may be kinked or piled.

Other methods known for the production of nonwoven fabrics may beutilized and include such processes as air laying, wet forming andstitch bonding. Such procedures are generally discussed in theEncyclopedia of Polymer Science and Engineering, Vol. 10, pp. 204-253(1987) and Introduction to Nonwovens by Albin Turbank (Tappi Press,Atlanta Ga. 1999), both incorporated herein in their entirety byreference.

The thickness of the nonwoven fabric may range from about 0.25 to 2 mm.The basis weight of the nonwoven fabric ranges from about 0.01 to 0.2g/in²; preferably from about 0.03 to 0.1 g/in²; and most preferably fromabout 0.04 to 0.08 g/in². The weight percent of first absorbablenonwoven fabric may range from about 10 to 80 percent, based upon thetotal weight of the reinforced absorbable multilayered fabric.

The second absorbable woven or knitted fabric functions as thereinforcement fabric and comprises oxidized polysaccharides, inparticular oxidized cellulose and the neutralized derivatives thereof.For example, the cellulose may be carboxylic-oxidized oraldehyde-oxidized cellulose. More preferably, oxidized regeneratedpolysaccharides including, but without limitation, oxidized regeneratedcellulose may be used to prepare the second absorbable woven or knittedfabric. Regenerated cellulose is preferred due to its higher degree ofuniformity versus cellulose that has not been regenerated. Regeneratedcellulose and a detailed description of how to make oxidized regeneratedcellulose are set forth in U.S. Pat. No. 3,364,200, U.S. Pat. No.5,180,398 and U.S. Pat. No. 4,626,253, the contents each of which ishereby incorporated by reference as if set forth in its entirety.

Examples of fabrics that may be utilized as the reinforcement fabricinclude, but are not limited to, Interceed® absorbable adhesion barrier,Surgicel® absorbable hemostat, Surgicel Nu-Knit® absorbable hemostat andSurgicel® Fibrillar absorbable hemostat (each available from Johnson &Johnson Wound Management Worldwide or Gynecare Worldwide, each adivision of Ethicon, Inc., Somerville, N.J.).

The reinforcement fabric utilized in the present invention may be wovenor knitted, provided that the fabric possesses the physical propertiesnecessary for use in contemplated applications. Such fabrics, forexample, are described in U.S. Pat. No. 4,626,253, U.S. Pat. No.5,002,551 and U.S. Pat. No. 5,007,916, the contents of which are herebyincorporated by reference herein as if set forth in its entirety. Inpreferred embodiments, the reinforcement fabric is a warp knitted tricotfabric constructed of bright rayon yarn that is subsequently oxidized toinclude carboxyl or aldehyde moieties in amounts effective to providethe fabrics with biodegradability.

In an alternative embodiment, the second absorbable woven or knittedfabric comprises oxidized polysaccharide fibers in combination withfibers comprised of aliphatic polyester polymers, copolymers, or blendsthereof.

The second absorbable woven or knitted fabric preferably comprisesoxidized regenerated cellulose and may have a basis weight ranging fromabout 0.001 to 0.2 g/in², preferably in the range of about 0.01 to 0.1g/in², and most preferably in the range of about 0.04 to 0.07 g/in².

The first absorbable nonwoven fabric is attached to the secondabsorbable woven or knitted fabric, either directly or indirectly. Forexample, the nonwoven fabric may be incorporated into the secondabsorbable woven or knitted fabric via needlepunching, calendaring,embossing or hydroentanglement, or chemical or thermal bonding. Thestaple of the first absorbable nonwoven fabric may be entangled witheach other and imbedded in the second absorbable woven or knittedfabric. More particularly, for methods other than chemical or thermalbonding, the first absorbable nonwoven fabric may be attached to thesecond absorbable woven or knitted fabric such that at least about 1% ofthe staple of the first absorbable nonwoven fabric are exposed on theother side of the second absorbable woven or knitted fabric, preferablyabout 10-20% and preferably no greater than about 50%. This ensures thatthe first absorbable nonwoven fabric and the second absorbable woven orknitted fabric remain joined and do not delaminate under normal handlingconditions. The reinforced absorbable multilayered fabric is uniformsuch that substantially none of the second absorbable woven or knittedfabric is visibly devoid of coverage by the first absorbabale nonwovenfabric.

One method of making the multilayered fabric described herein is by thefollowing process. Absorbable polymer fibers, having a denier per fiberof about 1 to 4, may be consolidated to about 80 to 120 deniermultifilament yarn and then to about 800 to 1200 denier yams, thermallycrimped and then cut to a staple having a length between about 0.75 and1.5 inch. The staple may be fed into a multiroller dry lay cardingmachine one or more times and carded into a uniform nonwoven batt, whilehumidity is controlled between about 40-60% at a room temperature of 60to 75° C. For example, the uniform nonwoven batt may be made using asingle cylinder roller-top card, having a main cylinder covered byalternate rollers and stripper rolls, where the batt is doffed from thesurface of the cylinder by a doffer roller and deposited on a collectorroll. The batt may be further processed via needlepunching or any othermeans such as calendaring. Thereafter, the first absorbable nonwovenfabric may be attached to the second absorbable woven or knitted fabricby various techniques such as needlepunching. The reinforced absorbablemultilayered fabric may then be scoured by washing in an appropriatesolvent and dried under mild conditions for approximately 30 minutes.

It is desirable to control process parameters such as staple length,opening of the staple, staple feed rate, and relative humidity. Forexample, the consolidated yarns may have from about 5 to 50 crimps perinch, and preferably from about 10 to 30 crimps per inch. Efficientcutting of the crimped yarns is desirable, as any long and incompletelycut staple tends to stick on the carding machine and cause pilling. Apreferred range of the staple length is from about 0.75 to 2.5 inches,and more preferably from about 1.5 to 2.0 inches.

To optimize uniformity and minimize the build-up of static electricity,the relative humidity may be controlled during batt processing,preferably during carding to form the uniform nonwoven batt. Preferably,the nonwoven batt is processed using a dry lay carding process at arelative humidity of at least about 40% at a room temperature of about60 to 75° C. More preferably, the nonwoven batt is processed at arelative humidity of from about 50% to 60%.

The multilayered fabric is scoured using solvents suitable to dissolveany spin finish. Solvents include, but are not limited to, isopropylalcohol, hexane, ethyl acetate, and methylene chloride. The multilayeredfabric is then dried under conditions to provide sufficient drying whileminimizing shrinkage.

The reinforced absorbable multilayered fabric may have an averagethickness of between about 0.75 and 3.0 mm, preferably between about1.00 and 2.5 mm, and most preferably between about 1.2 and 2.0 mm. Thebasis weight of the reinforced absorbable multilayered fabric is betweenabout 0.05 and 0.25 g/in², preferably between about 0.08 and 0.2 g/in²,and most preferably between about 0.1 and 0.18 g/in². The reinforcedabsorbable multilayered fabric is uniform such that there is no morethan about 10% variation (relative standard deviation of the mean) inthe basis weight or thickness across each square inch.

Additionally, the nonwoven fabric may comprise biologically activeagents, such as hemostatic agents. Hemostatic agents that may be usedinclude, without limitation, procoagulant enzymes, proteins andpeptides, either naturally occurring, recombinant, or synthetic. Morespecifically, prothrombin, thrombin, fibrinogen, fibrin, fibronectin,Factor X/Xa, Factor VII/VIIa, Factor IX/IXa, Factor XI/XIa, FactorXII/XIIa, tissue factor, von Willebrand Factor, collagen, elastin,gelatin, synthetic peptides having hemostatic activity, derivatives ofthe above and any combination thereof, may be utilized. Preferredhemostatic agents are thrombin, fibrinogen and fibrin.

Additionally, the nonwoven fabric may comprise pharmacologically andbiologically active agents, including but not limited to, wound healingagents, antibacterial agents, antimicrobial agents, growth factors,analgesic and anesthetic agents. When used as a tissue scaffold, thereinforced absorbable multilayer fabric may be seeded or cultured withappropriate cell types prior to implantation for the targeted tissue.

EXAMPLE 1 Nonwoven PGL Fabric with ORC Fabric.

Poly (glycolide-co-lactide) (PGL, 90/10 mol/mol) was melt-spun intofiber. A multi-filament yarn was consolidated, crimped and cut intostaple having a length of 1.75 inches. The staple was carded to create anonwoven batt and then compacted to a thickness of about 1.25 mm and adensity of about 98.1 mg/cc. The nonwoven fabric was then needlepunchedinto a knitted carboxylic-oxidized regenerated cellulose (ORC) fabric,available from Ethicon, Inc., under the tradename Interceede, to securethe nonwoven fabric to the ORC fabric. The final multilayered fabriccomprised about 60 weight percent of the nonwoven fabric.

EXAMPLE 2 Nonwoven PGL Fabric with ORC Fabric.

Poly (glycolide-co-lactide) (PGL, 90/10 mol/mol) was melt-spun intofiber. A multi-filament yarn was consolidated, crimped and cut intostaple having a length of 1.75 inches. The staple was carded to create anonwoven batt and then compacted to a thickness of about 1.22 mm and adensity of about 103.4 mg/cc. The nonwoven fabric was then needlepunchedinto a knitted carboxylic-oxidized regenerated cellulose fabric (ORC),available from Ethicon, Inc., under the tradename Surgicel NuKnit®, tosecure the nonwoven fabric to the ORC fabric. The final multilayeredfabric comprised about 25 weight percent of the nonwoven fabric.

EXAMPLE 3 Nonwoven PGL Fabric with ORC Fabric.

Poly (glycolide-co-lactide) (PGL, 90/10 mol/mol) was melt-spun intofiber. A multi-filament yarn was consolidated, crimped and cut intostaple having a length of 1.75 inches. The staple was carded to create anonwoven batt and then compacted a felt having a thickness of about 1.1mm and a density of about 102.8 mg/cc. The nonwoven fabric was thenneedlepunched into a knitted carboxylic-oxidized regenerated cellulosefabric (ORC), available from Ethicon, Inc., under the tradenameSurgicel®, to secure the nonwoven fabric to the ORC fabric. The finalmultilayered fabric comprised about 60 weight percent of the nonwovenfabric.

EXAMPLE 4 Nonwoven PGL Fabric with ORC Fabric.

Poly (glycolide-co-lactide) (PGL, 90/10 mol/mol) was melt-spun intofiber. A 80 denier multifilament yarn was consolidated into a 800 denierconsolidated 15 yarn. The consolidated yarn was crimped at approximately110 degree C. The crimped yarn was cut into staple having a length ofabout 1.25″ in length. 20 g of the crimped staple was accurately weighedand laid out uniformly on the feed conveyor belt of a multi-rollercarding machine. The environmental conditions (temp: 70 deg F/55% RH)were controlled. The staple was then carded to create a nonwoven batt.The batt was removed from the pick-up roller and cut into 4 equal parts.These were re-fed into the carder perpendicular to the collectiondirection. After this second pass the batt was weighed (19.8 g: 99%fabric yield) and then compacted into a felt. The compact felt wasprecisely laid onto an ORC fabric and firmly attached via 2 passes inthe needlepunching equipment. The multilayered fabric was trimmed andscoured in 3 discrete isopropyl alcohol baths to remove spin finish andany machine oils. The scoured multilayered fabric was dried in an ovenat 70 degree C for 30 minutes, cooled and weighed.

The “thickness” of the multilayered fabric was measured as describedherein. The measurement tools were:

-   (1) Mitutoyo Absolute gauge Model number ID-C125EB [Code    number—543-452B]. The 1″ diameter foot was used on the gauge.-   (2) A magnetic holder was used to lock in place and set the caliper    up to the die platen.-   (3) Two metal plates ˜2.75″×2″×0.60″, weighing between 40.8 g to    41.5 g [combined total of ˜82.18 g].

The multilayered fabric was placed on a platen surface that is a smoothand machined surface. The two metal plates were placed on top of eachother on the multilayered fabric and gently pressed at their corners tomake sure the multilayered fabric is flat. The gauge foot was placedonto the top of the metal plates and was then re-lifted and re-placed,at which time a reading was made.

12-1″×1″ pieces were die-cut from the scoured multilayered fabric andaccurately weighed. The thickness of each 1″×1″ piece was measured 4-5times in different areas of the metal plate in order to obtain areliable average. The weight and thickness of each piece is shown inTable 1. The values indicate that the coverage of both layers is similarin all directions. TABLE 1 Sheet #1 Sheet #2 Sample # Weight (g)Thickness (mm) Weight (g) Thickness (mm)  1 .132 1.53 .13 1.58  2 .1321.58 .124 1.57  3 .131 1.59 .13 1.62  4 .129 1.55 .134 1.64  5 .126 1.58.126 1.56  6 .125 1.5 .131 1.59  7 .129 1.56 .136 1.7  8 .127 1.52 .1311.62  9 .132 1.55 .131 1.57 10 .123 1.58 .136 1.58 11 .128 1.58 .1351.65 12 .13 1.51 .133 1.55 Average 0.1287 1.5525 0.1314 1.6025 Std. Dev0.0029 0.031 0.0037 0.044 CV (%) 2.304 2.002 2.837 2.767

Example 5 Effect of Humidity on Processing of Polyglactin 910 Staple.

80 denier polyglactin 910 consolidated yarn was crimped and cut into1.75 inch staple. Room temperature was maintained between 69-70° F. andthe relative humidity was controlled by a room humidifier and variedfrom 36-60%. Crimped staple was carded into a batt approximately 32″×8″.The percent of staple incorporated into the batt after two passesthrough the carding machine, i.e., the yield, increased with increasinghumidity, and the quality of the batt improved with yield. TABLE 2Effect of Relative Humidity on Processing Staple Batt Batt Weight (g) %RH Weight (g) Yield % Quality* 27 36 17 63 3.5 27 38-45 18.4 68 4.0 20.940 13.8 66 3.0 20.1 49 14.9 74 4.5 33 49 24.4 74 5.0 25.5 60 21.9 86 5.0*Quality was rated on a scale of 1-5 based on visual inspection.1 = large areas devoid of polyglactin 910, streaking pilling3 = some small bare spots devoid of polyglactin 910 or very thin spotswith minimal polyglactin 910 coverage5 = Uniform by visual inspection - no bare spots, no very thin spots, nopilling

Example 6 Effect of Staple Length on Processing of Polyglactin 910Staple.

80 denier polyglactin 910 consolidated yarn was crimped and cut into1.25″, 1.5″ and 1.75″ long staple. Room temperature was maintainedbetween 69-71° F. and the relative humidity was controlled at ˜55% by aroom humidifier. Crimped staple was carded into a batt approximately32″×8″. TABLE 3 Effect of staple length on batting quality and yield at55% RH Staple Staple Batt Batt Length (in) Weight (g) Weight (g) % YieldQuality* 1.75 25 13.94 56 4.0 1.75 25 16.0 64 5.0 1.5 30.7 28.0 91 ND1.5 25 21.8 87 ND 1.25 25 24.1 96 5.0 1.25 25 24.2 97 5.0*Quality was rated on a scale of 1-5 based on visual inspection.1 + large areas devoid of polyglactin 910, streaking, pilling3 = some small bare spots devoid of polyglactin 910 or very thin spotswith minimal polyglactin 910 coverage5 = Uniform by visual inspection - no bare spots, no very thin spots, nopilling.

EXAMPLE 7 Rotator Cuff Repair Using Reinforced Absorbable MultilayeredFabric.

In the case of a rotator cuff problem, the surgeon first looks at theextent of an injury using an arthroscope. Then, under generalanesthesia, the patient undergoes open surgery to repair the tear.

After the anesthetic has been administered and the shoulder has beenprepared, a cosmetic incision is made over the top front corner of theshoulder. This incision allows access to the seam between the front andmiddle parts of the deltoid muscle. Splitting this seam allows access tothe rotator cuff without detaching or damaging the important deltoidmuscle, which is responsible for a significant portion of the shoulder'spower. All scar tissue is removed from the space beneath the deltoid andthe acromion (part of the shoulder blade to which the deltoid attaches).Thickened bursa and the rough edges of the rotator cuff and humerus(upper arm bone) are also smoothed to make sure that they pass smoothlybeneath the acromion and deltoid.

The edges of the cuff tendons are identified and the quality andquantity of the cuff tissue is determined. The goal of the repair is toreattach good quality tendon to the location on the arm bone from whichit was torn. A groove or trough is fashioned in the normal attachmentsite for the cuff. To support the tendon and aid in healing, the surgeonsutures a patch of reinforced absorbable multilayered fabric into placeover it. Sutures (lengths of surgical thread) draw the edge of thetendon securely into the groove to which it is to heal.

The surgeon then completes the surgery by closing the deltoid muscle andthe skin incision. Over time, the body creates new tissue in the areathat matches surrounding tissue. The body also absorbs the implantedpatch in two to four months.

EXAMPLE 8 Knee Cartilage Repair Using Reinforced Absorbable MultilayeredFabric.

First, the surgeon examines the knee through an arthroscope—a smalldevice that allows the doctor to see into your knee joint. If a lesionis detected, a surgical procedure is performed.

After the anesthetic has been administered and the knee has beenprepared, a cosmetic incision is made through the skin over the topfront corner of the patella. First, the damaged cartilage is removed.The reinforced absorbable multilayered fabric is then implanted into thelesion. The fabric may be attached to the lesion site with sutures,tacks, or any of a number of biocompatible glues.

The surgeon then completes the surgery by closing the skin incision.Cartilage cells migrate into and multiply in the implanted fabric, andthe cell/fabric implant intergrates with surrounding cartilage. Withtime, the cells will mature and fill-in the lesion with hyalinecartilage.

While the examples demonstrate certain embodiments of the invention,they are not to be interpreted as limiting the scope of the invention,but rather as contributing to a complete description of the invention.All reinforcement fabrics described in the examples below are thenonsterile materials of the corresponding commercial products referredby their tradenames.

1. A method for making a multilayered fabric comprising a firstabsorbable nonwoven fabric and a second absorbable woven or knittedfabric, comprising the steps of. (a) crimping absorbable polymer fibersor yarns in the range of about 10 to 30 crimps per inch; (b) cutting thecrimped fibers or yarns to a staple length between about 0.1 and 2.5inch; (c) carding the staple to form the first absorbable nonwovenfabric; (d) attaching the first absorbable nonwoven fabric to the secondabsorbable woven or knitted fabric; while (e) controlling the humidityof the environment for step (c) to about 40 to 60%, at a roomtemperature of about 60 to 75° C.
 2. The method of claim 1, where thefirst absorbable nonwoven fabric comprises fibers comprised of aliphaticpolyester polymers or copolymers of one or more monomers selected fromthe group consisting of lactic acid, lactide (including L-, D-, meso andD, L mixtures), glycolic acid, glycolide, ε-caprolactone, p-dioxanone,and trimethylene carbonate.
 3. The method of claim 2, where the firstabsorbable nonwoven fabric comprises glycolide/lactide copolymer.
 4. Themethod of claim 2, where the second absorbable woven or knitted fabriccomprises oxidized polysaccharides.
 5. The method of claim 4, where thesecond absorbable woven or knitted fabric comprises oxidized cellulose.6. The method of claim 5, where the second absorbable woven or knittedfabric comprises oxidized regenerated cellulose.
 7. The method of claim5, where the second absorbable woven or knitted fabric is an absorbableknitted fabric comprising oxidized regenerated cellulose.
 8. The methodof claim 1, where the first absorbable nonwoven fabric comprisesglycolide/lactide copolymer, and the second absorbable woven or knittedfabric comprises oxidized regenerated cellulose.
 9. The method of claim8, where the first absorbable nonwoven fabric comprises staple having alength from about 0.75 to 2.5 inches.
 10. The method of claim 9, wherethe first absorbable nonwoven fabric comprises staple having a lengthfrom about 1.5 to 2.0 inches.
 11. The method of claim 8, where the firstabsorbable nonwoven fabric comprises a copolymer of glycolide andlactide, in an amount ranging from about 70 to 95% by molar basis ofglycolide and the remainder lactide, and the second absorbable woven orknitted fabric comprises oxidized regenerated cellulose.
 12. The methodof claim 11, where the first absorbable nonwoven fabric is attached tothe second absorbable woven or knitted fabric via needlepunching. 13.The method of claim 12, where the absorbable polymer fibers range fromabout 1 to 4 denier per filament.
 14. The method of claim 13, where thefirst absorbable nonwoven fabric has a basis weight of about 0.01 to 0.2g/in²; and the second absorbable woven or knitted fabric has a basisweight of about 0.001 to 0.2 g/in²
 15. The method of claim 1, whereinthe first absorbable nonwoven fabric is attached to the secondabsorbable woven or knitted fabric via needlepunching.